Locomotive reverse gear



Oct. 17, 1933. E. W. .ALBERS 1,930,636 l LOCOMOTIVE REVERSE GEAR Filed Dec. 2l, 1952 2 Sheets-Sheet l 30 I6 2.2 t: NVENTOR 3 w Edwin w19/bers Oct. 17, 1933. E W ALBERS LOCOMOTIVE REVERSE GEAR Filed Dec.

21, 1932 2 Sheets-Sheet 2 INVENTOR BY Edwin Wfl/bers NEY Patented Oct. 17, 1933 LUNITED -STATES PATENT?A OFFICE Application December 21, 1932 Serial No. 648,156

2 Claims.

This invention relates to power operated reverse gears for steam locomotives, and particularly to a reverse gear operated by iiuid pressure.

An object of the present invention is to provide 5 an improved reverse gear, embodying liquid pressure operating means wherein the operating liquid, i. e. water, under pressure is taken directly from the locomotive boiler.

Another object of the invention is to provide a device of the character described wherein an incompressible operating liquid is retained within the power cylinder of the reversegear and utilized to maintain a denite adjustment of the reverse gear so as to prevent the adjustment from being affected by sudden shocks and disturbances produced by the steam distribution valve gear.

Another object of the invention is to provide a device of the character described wherein fluid taken from the locomotive boiler` either steam or water, will be circulated around the reverse gear power cylinder to maintain the working fluid, when the latter is heldwithin the power cylinder, at at least its initial temperature, in order to avoid a cooling of the liquid within the power cylinder, which cooling would produce an undesirable play in the operation of the gear after its adjustment.

Another object of the invention is to provide a device of the character described embodying an integral construction of water jacket housing for the power cylinder in combination with a bracket comprising attaching means for the dev1ce.

Another object is to provide in one form of the invention an improved device of the character described wherein the power cylinder comprises a steel tube.

Another object of the invention is to provide a device of the character described wherein the body of the control valve for the power cylinder and a. head for the cylinder are constructed as an integral casting.

Another object is to provide in another form of the invention, a device of the character described embodying a power cylinder and a supporting bracket therefor formed as an integral casting.

Another object of the invention is to provide a device of the character described embodying a control valve operating mechanism adapted for operation by considerably less than the usual amount of travel of the floating lever, which receives motion from a connecting rod attached to the reverse shaft arm of the locomotive.

Other and further objects and advantages achieved by the present invention will be apparent from the following detailed description of embodiments thereof. l

As is well-known in practice, the generally used design of reverse gear is operated by compressed air taken from the same supply that is used for the operation of the locomotive air brakes. This air is fed through an operating valve and piping which forms a part of the power reverse gear, and is used to impart the desired movement to a piston operating within the reverse gear power cylinder. While by this use of air under pressure, a desirable cushioning eiiect is obtained, which tends to absorb shocks imparted by the distribution valve gear, nevrtheless, when the valve is set and compressed air is trapped in the cylinder on both sides of the reverse gear piston, the condition which results is essentially the same as if springs under compression were disposed one on each side of the piston, and the ability of the reverse gear piston, therefore, to remain in a xed position is resisted only by the friction of the piston working in the cylinder, and by the friction of the piston rod working through the packing, at its bearing. This 8o friction is insuflicient to withstand the shocks produced by the valve gear, and while the reverse gear mechanism is designed to immediately correct any misadjustments of the reverse gear, its eiiiciency is limited, and it has been found that the necessary constant readjustment results in a creeping action. That is to say, the original setting of the reverse gear vfor a definite cut-oi adjustment for the main valve gear is not accurately maintained, resulting in changes in the cut-off of the distribution valve from that desired.

Further, in the use of a compressed air operated reverse gear, such as aforedescribed, occasional delays occur, if the reverse gear is to be adjusted immediately after a brake application has taken place which application results in a reduction of the air pressure to a point insuflicient for operating the reverse gear. It is then necessary to wait until the main air reservoir l pressure is built up suiiiciently to operate the reverse gear. In the embodiment of the present invention where the reverse gear is operated by water under pressure taken from the locomotive boiler, full boiler pressure is practically always I available whenever any reverse gear adjustment is necessary, so that the aforementioned delays do not occur.

The present invention provides means for overcoming the above mentioned creeping action of the reverse gear, and provides an arrangement whereby, when an adjustment has once been made, the reverse gear will be maintained fixed, in such adjusted position, thereby securing the desired permanency of the cut-off adjustment. This is accomplished in the present invention by the provision of a structure wherein, when the control valve is closed, water is locked within the power cylinder on both sides of the piston, and acts as a solid medium, as water, whether at high or low temperatures, is practically incompressible.

The present invention is of particular advantage for use with large locomotives of such designs as are now in general use, which operate with a pressure of 250 pounds or more, the present invention making available for the operation of the reverse gear this relatively high pressure, as against the former use of air pressure of approximately 110 pounds.

The use of the higher pressure makes possible the use of a reverse gear cylinder of reduced size to eifect the same power, for instance, considering the respective water and air pressures above mentioned, a seven inch diameter cylinder operated by the higher water pressure will do the same work as a ten inch diameter cylinder operated by the lower air pressure. Furthermore, the volurne of water displaced by the water operated reverse gear piston is substantially less than the volume of air that is displaced by the air operated piston, so that by employing the usual size ports and passages in the water operated reverse gear, a reverse gear capable of a relatively substantially speedier operation results.

The invention is illustrated in the accompanying drawings wherein Fig. 1 is a side view of a part of a locomotive embodying the present invention; Fig. 2 is a longitudinal section, on an enlarged scale, on the line II-II of Fig. 4, of the power cylinder construction and control valve of the reverse gear mechanism shown in Fig. 1; Fig. 2a is a longitudinal section of a modified form of the control valve for the power cylinder; Fig. 3 is a plan view of the structure shown in Fig. 2; Fig. 4 is a forward end view of the structure shown in Fig. 2; Fig. 4a is a fragmentary forward end view of a modified arrangement of the structure shown in Fig. 4 in connection with which the modified form of control valve shown in Fig. 2a is employed; Fig. 5 is a section on the line V-V of Fig. 2; Fig. 6 is a transverse sectional view of a power cylinder construction similar to that shown in Fig. 5, but having a modified supporting bracket arranged for connection with a locomotive bed; Fig. 7 is a plan view of the structure shown in Fig. 6; Fig. 8 is a longitudinal section of an end of a power cylinder and housing similar to that shown in Fig. 2, but with the cylinder welded to the housing at the rearward end thereof; Fig. 9 is an inside View, on an enlarged scale, of the valve seat shown in Fig. 2; and Fig. 16 is a section on the line X-X of Fig. 9; Fig. 10a is a side view of the valve element of the control valve.

Referring in detail to the drawings, and particu, larly to Figs. 1 to 5, a steam locomotive, indicated generally by the numeral 1, is provided with reverse gear mechanism of the present invention, indicated generally by the numeral 2. The reverse gear mechanism comprises a power cylinder construction 3, which includes a steel tube or cylinder 4, which engages a steel rear cylinder head 5. The cylinder 4 is surrounded by a cylindrical housing 6 for a water or steam jacket, having a bracket '7 integrally cast therewith. The bracket 7 is shaped to conform with the Curva-- of the housing 6, and is secured thereto by studs 9.

At the forward end of the power cylinder construction 3 a ring 10 is provided around the cylinder 4, and is attached to the cylinder 4 by welding at 11. The housing 6 is provided near its forward end with an interior inwardly extending flange 12 which provides a seat for the ring 10. A front cylinder head and valve body structure 13 is provided for the power cylinder construction 3, and embodies, as an integral casting, a cylinder head portion 14, a stufling box 15, and a valve seat and port housing 16. The housing 6, at its forward end, is provided with an outwardly extending peripheral flange 17, and the structure 13 is secured to the housing by studs 18 passed through its peripheral margin into said ange. On the inner face of the head portion 13 a circular inwardly extending seat 19 is formed. The seat 19 bears against the ring 10, securely holding the housing 6, cylinder 4, and structure 13 in engagement. Suitable packing rings 20 are provided on opposite sides of the ring 10 to ensure a water tight fit.

A piston 21 is disposed within the cylinder 4, and adapted to reciprocate longitudinally therein. A piston rod 22 is connected to the piston 21, and extends through a central opening 23 formed in the head portion 14, and extends forwardly and out through the stuffing box 15. A gland 24 is provided around the piston rod 22, and extends into the stuffing box 15, suitable packing being provided within the stufling box around the piston rod and being held underpressure by the gland 24. The gland is provided with an outwardly extending ange 25 suitably secured to the stufng box by studs 26 in the usual manner.

The piston rod 22 is pivotally secured, at its forward end, to a reach rod 2'7, which is in turn pivotally connected at its forward end, to a reverse shaft arm 28. The reverse shaft is connected, in the usual manner, with valve gear and distribution valves (not shown) of the locomotive, and adapted to adjust the valve gear and distribution valve for variable cut-off.

The valve seat and port housing 16 (Figs. 2, 9 and 10) is provided with ports 29 and 30, connected with the front and rear ends of the power cylinder 4, respectively, an inlet port 31 connected by means of a pipe 32 to the locomotive boiler, and an exhaust port 33 connected by means of a pipe 34 to the locomotive boiler feed water pipe 35, from which it is fed to the boiler by an injector 35a, through pipe 36 and a check valve 37 provided in the usual manner.

It will be apparent that a separate injector is unnecessary for the operation of the present invention, and that the injector 35a will usually be the ordinary injectorof the locomotive boiler, the exhaust from the exhaust port of the control valve being carried into the regular main feed water line of the locomotive boiler, or if desired, to any other suitable connection for taking care of the exhaust from the power. cylinder.

The valve seat is provided with a cap 38, and a valve element 39 (Fig. 10a) disposed within the cap, a retainer 40 for the valve element, a valve stem 41, and a spring 42 for forcing the valve element against the seat beingalso provided, all O f the usual construction and arrangement. The

valve element is provided with the usual cavity 43 by means of which the ports 31 and 33 may be selectively connected, upon the turning of the valve element on the seat, with the respective ports 29 and 30 leading to opposite ends of the Vworking cylinder, for supplying and exhausting fluid therefrom in the usual manner to reciprocate the piston. It will be apparent that when the valve element is in a set, or closed, position after a definite desired adjustment of the position of the piston has been made, and consequently the distribution valve gear has been brought to the desired adjustment, the valve element will cover, or close, both of the ports 29 and 30 thus confining the water within the opposite ends of the cylinder, so as to rigidly hold the piston against movement.

A floating lever 44 is pivotally connected between its ends to the upper end of an arm 44a. 'Ihe arm 44a is operably connected at its lower end to the valve stem 41. The upper end of the lever 44 is pivotally connected to the forward end of a reach rod 45, the rear end of the reach rod being pivotally connected with a hand reverse gear operating lever 46 within the locomotive cab. The lower end of the floating lever 44 is pivotally connected to the rear end of a connecting rod 47, and the forward end of the rod 47 is pivotally connected to the reverse shaft arm 28 between the ends thereof.

As a modified arrangement of the last described structure the arm 44a may be arranged as shown in Fig. 4a, that is, operably connected with the valve stem at its upper end, extending downwardly, and pivotally connected at its lower end to the lever 44 intermediate the ends of the lever. For use with this construction a modified form of valve seat and port housing will necessarily be employed. Such valve seat and port housing is illustrated in Fig. 2a Aindicated generally by the designation 16a, and is identical in form with the valve seat and port housing 16 shown in Fig. 2 excepting that the ports in the housing 16a are differently arranged. The valve element for the housing 16a will, of course, be so adjusted as to bring the proper ports into communication. The ports and connecting pipes of the housing 16a corresponding to the respective parts of the housing 16 and pipes connected therewith are indicated by the same reference numerals with the letter a added thereto.

The control valve of the present invention functions in the usual manner, and is of the same general design as the valves ordinarily used for air operated reverse gears, excepting that the lower end of the floating lever 44 is, in the present instance, operated with one-half of the usual travel. That is to say, in designs heretofore employed, the lower end of the floating lever has derived its motion from a cross head attached to the reverse gear piston rod. This reduced travel of the iioating lever of the present invention results, as aforedescribed, by virtue of the lower end of the lever being connected, by a connecting rod, to the reverse shaft arm 28, between the ends thereof.

The embodiments illustrated are suitable for a valve gear of the Walschaert type, but it will be understood that the reduced travel may also be obtained where reverse gear of other designs are employed, as for instance when a gear of the Baker type is employed, an auxiliary arm may be formed as in integral part of the reverse shaft and the connecting rod 47 connected thereto.

The return pipe 48 from the housing 6 preferably leads to a lower` part of the locomotive boiler,

prevented. A check valve 50 is interposed in the supply pipe 32, so that the Water supplied to the reverse gear valve will always be drawn from the highest point on the boiler. It is of course within the contemplation of the present invention to arrange the housing connecting pipes so as to use steam for the water jacket of the p'ower cylinder.

By virtue of the construction of the power cylinder 4 as a steel tube with the ring 10 welded thereto, as heretofore described with reference to Fig. 2, the power cylinder may be readily removed. Another connecting arrangement for the cylinder 4, however, is illustrated in Fig. 8 wherein the cylinder 4 is permanently sealed to the water jacket housing 6a, at the rear end by welding at 51. In this instance, the forward end (not shown) of .the cylinder construction will be the same as that described with reference to Fig. 2. In this instance, however, the rear end of the housing 6a is formed with an annular longitudinally projecting seat 52 at its inner periphery, and the rear cylinder head 53 is provided with a circular groove 54 into which the seat 52 extends. The head 53 is secured to the housing 6a by studs 55.

In Figs. 6 and 7, there is illustrated a modified form of the housing and bracket construction. Here the bracket 7a is integrally cast with the housing 6b similarly to the housing 6 and bracket 7, but in this embodiment the bracket '7a is arranged to present bolting members 56 and 57, arranged at right angles to each other, and adapted for connection to the main frame of the locomotive.

While there has been hereinbefore described certain preferred embodiments of the present invention, it will be understood that many and various changes and modifications in form, structure, design, and arrangement may me made without departing from the spirit of the present invention, and that all and any such changes and modifications as fall within the scope of the appended claims are contemplated as part of the present invention.

'Ihe invention claimed and desired to be secured by Letters Patents is:

1. In a locomotive, the combination of a boiler; a reverse shaft arm; and a power reverse gear mechanism comprising a piston, a piston rod connected with said arm for effecting adjustment thereof, a jacketed cylinder for said piston, a control valve for said cylinder having cylinder ports communicating with the opposite ends of said cylinder and an exhaust port, a pipe connecting said valve with said boiler below its water line, whereby power water is fed from said boiler to said opposite ends of said cylinder and said cylinder on each side of the piston is continually filled with water, said valve having a valve element operable to close said cylinder ports against ingress or egress of water to hold said piston in adjusted placement, means for operating said valve element to selectively open said cylinder ports to exhaust and supply to actuate said piston for adjustment-thereof, and thereafterto return said element to cylinder port closing position, an inlet pipe connecting the jacket of said cylinder with said boiler for feeding boiler contents to said jacket, and an outlet pipe connecting said jacket to said boiler for returning said contents thereto whereby circulation of said contents through said jacket will be maintained and the entrapped water in said cylinder will be maintained at at least its initial temperature to prevent contraction of the water therein and consequent possible displacement of said piston and reverse shaft arm.

2. In a locomotive, the combination of a boiler; a reverse shaft arm; and a power reverse gear mechanism comprising a piston, a piston rod connected with said arm for effecting adjustment thereof, a jacketed cylinder for said piston, a control valve for said cylinder having cylinder ports communicating with the opposite ends of said cylinder and an exhaust port, a pipe connecting said valve with said boiler below its water line, whereby power water is fed from said boiler to said opposite ends of said cylinder and said cylinder on each side of the piston is continually filled with water, said valve having avalve element operable to close said cylinder ports againstingress or egress of water to hold said piston in adjusted placement, means for operating said valve element to selectively open said cylinder ports to exhaust and supply to actuate said piston for adjustment thereof, and thereafter to return said element to cylinder port closing position, means connecting said exhaust port with said boiler including means for forcing water therein into said boiler, an inlet pipe connecting the jacket of said cylinder with said boiler for feeding boiler contents to said jacket, and an outlet pipe connecting said jacket to said boiler for returning said contents thereto whereby circulation of said contents through said jacket will be maintained and the entrapped water in said cylinder will be maintained at at least its initial temperature to prevent contraction of the water therein and consequent possible displacement of said piston and reverse shaft arm.

EDWIN W. ALBERS. 

